RT Journal Article
SR Electronic
T1 Free light chains of immunoglobulins in patients with systemic sclerosis: correlations with lung involvement and inflammatory milieu
JF Journal of Clinical Pathology
JO J Clin Pathol
FD BMJ Publishing Group Ltd and Association of Clinical Pathologists
SP 620
OP 625
DO 10.1136/jclinpath-2017-204656
VO 71
IS 7
A1 Bosello, Silvia
A1 Basile, Umberto
A1 De Lorenzis, Enrico
A1 Gulli, Francesca
A1 Canestrari, Giovanni
A1 Napodano, Cecilia
A1 Parisi, Federico
A1 Pocino, Krizia
A1 Di Mario, Clara
A1 Tolusso, Barbara
A1 Ferraccioli, Gianfranco
A1 Gremese, Elisa
YR 2018
UL http://jcp.bmj.com/content/71/7/620.abstract
AB Aim Humoral immunity and B cells are thought to play an important role in the pathophysiology of the systemic sclerosis (SSc). The production of free light chains (FLC) of immunoglobulins is abnormally high in several pathological autoimmune conditions and reflects B cell activation. Furthermore, FLCs demonstrated different biological activities including their capability to modulate the immune system, proteolytic activity and complement cascade activation. The aims of this study are to determine the FLC levels in patients with SSc compared with healthy controls (HC) and to study their possible association with organ involvement and disease characteristics.Methods Sixty-five patients with SSc and 20 HC were studied. Clinical and immunological inflammatory characteristics were assessed for all the patients with SSc. κ-FLC and λ-FLC, interleukin 6 (IL-6) and B cell activating factor levels were measured.Results The mean serum κ-FLC levels and FLC ratio were significantly higher in patients with SSc compared with HC, while the serum λ-FLC levels were comparable.The levels of FLC were comparable in patients with diffuse skin disease and limited skin involvement, while κ-FLC levels were increased in patients with restrictive lung (forced vital capacity (FVC) <80%) disease (26.4±7.4 mg/L) when compared with patients with FVC ≥80% (19.6±7.3 mg/L, P=0.009). In patients with SSc, the levels of serum κ-FLC level directly correlated with the IL-6 levels (R=0.3, P=0.001) and disease activity (R=0.4, P=0.003).Conclusions FLC levels are elevated in SSc and high levels are associated with lung involvement and with a higher degree of inflammation, supporting a possible role of B cell activation in the pathophysiology of the disease.